Officials such as police officers, customs agents and the like often encounter suspect materials which are thought to contain one or more controlled substances such as illicit drugs. This encounter usually occurs under field conditions. It is often necessary to establish the nature of the suspicious substances on the spot so as to be able to detain or apprehend a suspected individual. For a number of other reasons as well, it is impractical for police or customs officers to send suspicious material to the agency's laboratories. A test of the material must be done in the field and results must usually be obtained within minutes.
Today testing for the presence or absence of illicit drugs is known as is their identification. The quickest tests known for drug detection and identification are color tests in which the response of a drug to a specific reagent is a color change. At times only the class of drug is identified; at other times the specific drug is determined. The method of testing for the presence of a drug usually requires mixing or contacting a reagent with the substance to be tested. Most if not all of the color test reagents used today are available commercially, individually or as one of a series of reagents in a multi-reagent kit.
Commonly known chemical reagents for color change testing for the presence or absence of illicit drugs include, but are not limited to, Meyer's reagent (phenolthalein/sodium hydroxide), Marquis reagent (sulfuric acid/formaldehyde), Nitric acid reagents, Cobalt thiocyanate reagent, Dille-Koppanyi reagent (cobalt acetate dehydrate/methanol/glacial acetic acid), Mandeline reagent (ammonium vanadate/sulfuric acid), Mecke's modified reagent (selenous acid/sulfuric acid), Duquenois-Levine reagent (acetaldehyde/vanillin/ethanol), Simon's reagent (sodium nitroprusside/acetaldehyde) and Zwikker's reagent (copper sulfate pentahydrate/pyridine). Classes of controlled drugs which are detectable through reagent color testing include, but are not limited to, barbiturates, amphetamines, opiates, and synthetic opiates. The National Institute of Justice (NIJ) has issued a standard through its law enforcement and correction standards and testing program called Color Test Reagents/Kits for Preliminary Identification of Drugs of Abuse (NIJ Standard-0604.01). This standard summarizes many drug testing procedures and reagents.
However, the performance of chemical reagent drug tests suffers from a number of drawbacks and deficiencies. From the above NIJ pamphlet and other sources it is evident that in order to test for all of the possible controlled illicit drugs, a kit containing many reagents, some of which are caustic or corrosive, is required.
Performing the tests is often potentially hazardous. For instance, many tests typically require one or more steps and the manipulation of various vials, which can be time consuming, inconvenient and dangerous. The aforementioned steps may result in mishaps and spillage of liquids which, as noted above, may be caustic or otherwise corrosive.
Currently, a few kits for testing and identifying a wide range of illicit drugs under field conditions exist. However, because the materials generally used for testing suspected materials are drug specific, a relatively large number of reagents and physical operations are still required to cover the wide range of drug possibilities when a sample is of unknown identity.
Importantly, use of the reagents and kits currently available often requires appreciable amounts of suspected material, usually an amount at least visible to the naked eye. Trace amounts of illicit materials often go undetected.
It would therefore be desirable to provide a test for field use wherein the number of reagents and tests is minimized. It would also be desirable to provide a field test kit where a minimum number of physical operations is required, reducing possible mishaps, inaccurate readings and spillage of liquids. It would also be desirable to provide field test kits where no caustic or corrosive reagents are present. Finally, it would be desirable to provide a field test kit suitable for identifying very small size samples.